Ultrasensitive Boron-Nitrogen-Codoped CVD Graphene-Derived NO₂ Gas Sensor

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Sensing

Background:

• Two-dimensional (2D) materials, such as graphene, are crucial for developing advanced portable devices.
• Heteroatom doping in graphene's hexagonal lattice is a key strategy to enhance material properties for applications like gas sensors.

Purpose of the Study:

• To investigate the potential of codoping graphene with boron and nitrogen for improved gas sensing capabilities.
• To develop and demonstrate a boron- and nitrogen-codoped bilayer graphene (BNGr) gas sensor for enhanced nitrogen dioxide (NO2) detection.

Main Methods:

• Synthesis of BNGr using low-pressure chemical vapor deposition (LPCVD).
• Characterization of BNGr using Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and Field Emission Scanning Electron Microscopy (FESEM).
• Fabrication of a gas sensing device on a Si/SiO2 substrate with gold electrodes and performance evaluation at room temperature.
• Exploration of the NO2 gas sensing mechanism using Density Functional Theory (DFT) calculations.

Main Results:

• Successful synthesis of BNGr confirmed by Raman, XPS, and FESEM, verifying graphene nanosheets and codoping.
• The BNGr sensor exhibited ultrasensitive detection of NO2 at room temperature.
• DFT calculations provided insights into the sensing mechanism involving adsorption on doped heteroatom sites.

Conclusions:

• Boron- and nitrogen-codoped bilayer graphene demonstrates significant potential for ultrasensitive NO2 gas sensing.
• This research offers a new pathway for designing next-generation lightweight and highly sensitive gas sensing devices.